High Frequency Data Link (HFDL)

From Signal Identification Wiki
Jump to: navigation, search

High Frequency Data Link (HFDL)
HFDL.jpg
Frequencies 2.9 MHz,22 MHz
Frequency Range 2.9 MHz - 22 MHz
Mode USB
Modulation PSK
ACF
Bandwidth 2.4 kHz
Location Worldwide
Short Description HFDL, also known as HF-ACARS, ARINC 753, ARINC 635, and HF DATALINK,is a data link that aircraft use to communicate short messages over long distances using HF signals.
I/Q Raw Recording
Audio Sample

HFDL, also known as HFHigh Frequency (3-30 MHz)-ACARS, ARINC 753, ARINC 635, and HFHigh Frequency (3-30 MHz) DATALINK,is a data link that aircraft use to communicate short messages over long distances using HFHigh Frequency (3-30 MHz) signals. HFDL is defined in ARINC spec 753.

Transmissions on HFHigh Frequency (3-30 MHz) are in USBUpper Side Band Modulation (Radio, referring to reception and modulation mode)Universal Serial Bus (Computer, referring to USB Ports and cables) on a sub-carrier of 1440 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz). with a symbol speed of 1800 baudBaud (unit symbol Bd) is the unit for symbol rate or modulation rate in symbols per second.. Data is sent at 300, 600, 1200 or 1800 bpsBits per second (bps). HFDL can use BPSKBinary Phase-Shift Keying (1 bit per symbol), QPSKQuadrature Phase-Shift Keying (2 bits per symbol), and 8-PSK8-Phase Phase-Shift Keying (3 bits per symbol).


Frequencies[edit]

A more up to date sites listing of HFDL frequencies can be found here as a zip file. It also contains a file that can be used in the registered version of PC-HFDL.

Samples[edit]

300 bpsBits per second (bps) Short (BPSKBinary Phase-Shift Keying (1 bit per symbol))

600 bpsBits per second (bps) Long (BPSKBinary Phase-Shift Keying (1 bit per symbol))

1200 bpsBits per second (bps) Short (QPSKQuadrature Phase-Shift Keying (2 bits per symbol))

Additional Samples[edit]

Decoding Software[edit]

Hobby Level Software


Professional Equipment/Software

Video Examples[edit]

Additional Links[edit]

Additional Images[edit]